Method and apparatus for re-approximating tissue

ABSTRACT

Methods and apparatuses are described for attaching tendons, ligaments, or other tissue to bone, which includes the use of adjustable head members positioned along filament members. Also disclosed are methods and apparatuses for mending breaks in tissue such as skin or meniscal layers tissue such as skin or meniscal layers skin by use of similar elements.

This is a continuation of application Ser. No. 609,886, filed Nov. 6,1990, now U.S. Pat. No. 5,372,146.

TECHNICAL FIELD

This invention relates in general to surgically-related methods andapparatuses, and more particularly relates to methods and apparatusesfor re-approximating, or re-attaching, a tendon or ligament to a bone,when the same have become separated due to injury or othercircumstances. The invention also relates to methods and apparatuses forreattaching tissue such as skin edges or meniscal layers after suchtissue has been torn, cut, or otherwise severed. Due to the relativelysimple embodiments of the present invention, the invention also may beused in conjunction with arthroscopic procedures, minimally invasivesurgical procedures utilizing tiny incisions and a fiber optic camera.

BACKGROUND OF THE INVENTION

In surgical practice, a genuine need often exists for a reliable,simple, and effective means for re-attaching tendons, ligaments, orother tissue which have become separated from the bone of a human oranimal. Such separation may be due to injury, genetic defects, or may bethe result of various surgical procedures.

It is preferable to re-attach such a tendon or ligament to the bone suchthat it may eventually heal and attach itself to the bone. In such aconfiguration, it may be understood that the attachment of the ligamentor tendon to the bone must be sufficient to withstand loads seen duringrehabilitation, which may include loads necessitated by physicaltherapy.

If the tendon or ligament cannot be attached to the bone such thatgrafting would occur, the attachment must be sufficient to withstandloads encountered not only during rehabilitation, but for the rest ofthe-patient's life.

It may be understood that particular needs are presented by suchre-attachment requirements, such as a need to expediently perform there-attachment procedure in order that the patient undergoes minimaltrauma, as well as a need to provide a minimally-sized incision, inorder to reduce the risk of infection and to minimize scarring.

A number of prior art methods and devices have been developed in orderto address the above-discussed needs. However, the prior art known tothe applicant does not adequately satisfy these needs.

It is known to utilize pliable sutures in order to attach tissue tobone, or tissue to tissue, by passing the suture through or around suchelements, and subsequently hand tying the sutures in place. However,such methods are disadvantageous as it is difficult to determine theproper mount of tension to be applied to the sutures such that thesutures maintain adequate holding strength but do not break. Otherdisadvantages arise in that the space allowed to perform such tyingtechniques may be generally limited.

It is also generally known to staple ligaments or tendons to a bone,although such a method has significant drawbacks. If the staple ispositioned too loosely, the ligament or tendon may become detached byslipping underneath the staple. If the staple is positioned too tightlyon the bone, the ligament or tendon may be severed or "guillotined" bythe staple, or disadvantageous tissue necrosis or death may occur.

U.S. Pat. No. 4,708,132 to Silvestrini, entitled "Fixation Device for aLigament or Tendon Prosthesis", issued Nov. 24, 1987, discloses a devicefor affixing a pretensioned ligament or tendon prosthesis to a bone of apatient. It may be seen that a relatively complex anchor device isutilized, which requires the drilling of holes completely throughvarious bones of the patient, necessarily requiring extensive surgicalprocedures.

U.S. Pat. No. 4,784,126 to Hourahane, entitled "Surgical Device", issuedNov. 15, 1988, discloses another method for surgery of which requiresdrilling of hole completely through a bone of a patient, such that onelongated clamp may be passed through the rear opening of the hole, inorder to clasp a ligament and draw it through the front opening of thehole.

U.S. Pat. No. 5,482,451 to Moore, entitled "Glenohumeral LigamentRepair", issued Oct. 10, 1989, discloses a ligament repair kit andprocedure for installing a. cannulated bone screw and ligament washer toretain a ligament on a bone. Further disclosed is a screw which isscrewed to tighten a spiked ligament washer against the displacedligaments to firmly hold them in place against the bone.

U.S. Pat. No. 4,889,110 to Galline et at., entitled "Attaching Deviceand Tools for Positioning Same, Especially for Attaching TrochanterMajor to the Femur", issued Dec. 26, 1989, discloses an attaching deviceincluding an anchoring plate having four bores which receive twocrimping tubes and two crimping rings for holding a multi-ply cable. Thedevice is adapted to be used for attaching the trochanter major to thefemur in the case of a trochanteric osteotomy.

Although at least some of the above patents do generally discloseattachment of a detached ligament to a bone, they include disadvantagesin that they utilize complex attachment devices and procedures.Furthermore, the disclosed techniques require in some cases severesurgical incisions in order to access patient bone areas for drilling,which may disadvantageously cause patient trauma, unacceptable scarring,or infection.

Therefore, there is a need in the art to provide a reliable, simple, andeffective means for re-attaching a tendon or ligament to a bone, inwhich minimal patient trauma is encountered, and minimum infection orscarring results.

SUMMARY OF THE INVENTION

The present invention addresses the above-discussed deficiencies in theprior an by providing a reliable, simple, and effective means forattaching a tendon or ligament to a bone, with a minimum of patienttrauma, exposure to infection, and scarring.

Generally described, a method according to the present inventioncomprises the steps of attaching a first end of a flexible, elongate,filament member to a bone, the filament member including a firstprotruding portion, and including a first reduced portion intermediatethe first end and the first protruding portion, and defining a secondend opposing the first end; threading the second end of the filamentmember through an internal hole defined by a head member, the headmember also defining engagement means extending into the hole, theengagement means configured to engage the first protruding portion to agreater extent than the tint reduced portion; urging the head memberalong the filament member toward the first end and away from the secondend with a force sufficient to urge the engagement member across theprotruding section of the filament member until the engagement member ispositioned atop the reduced section and the tissue member is capturedbetween the head member and the bone.

Therefore it is an object of the present invention to provide a methodand apparatus for re-attaching tendons, ligaments, or other tissue tobone.

It is a further object of the present invention to provide a method andapparatus for repairing a skin break.

It is a further object of the present invention to provide a method andapparatus for re-attaching tendons, ligaments, or other tissue to bonewhile providing minimal exposure to infection.

It is a further object of the present invention to provide a method andapparatus for re-attaching a tendon, ligament, or other tissue to a bonewhich do not require complete drilling through the bone.

It is a further object of the present invention to provide a method andapparatus for re-attaching a tendon, ligament, or other tissue to a bonewhich are especially suitable for use in conjunction with arthroscopicprocedures.

It is a further object of the present invention to provide a method andapparatus for re-attaching severed tissue which are especially suitablefor use in conjunction with arthroscopic procedures.

It is a further object of the present invention to provide a method andapparatus for re-attaching a tendon, ligament, or other tissue to a bonewhich require a minimal amount of surgical incision.

It is a further object of the present invention to provide a means forre-attaching a tendon, ligament, or other tissue to a bone, which allowsthe tissue to eventually graft to the bone.

Other objects, feature, and advantages of the present invention willbecome apparent from reading the following specification when taken inconjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side view of a fastening system including a filament memberand a head member mounted thereon.

FIG. 2 is a more detailed view of the interaction of the head member andthe filament member illustrated in FIG. 1.

FIG. 3 is a side view of a second fastening system including a filamentand a head member mounted thereon.

FIG. 4 is a more derailed view of the interaction of the head member andthe filament member illustrated in FIG. 3.

FIGS. 5 and 6 are other detailed views similar to that of FIG. 4,illustrating other filament-head configurations.

FIG. 7 is detailed view of a filament member having a substantiallyconstant transverse cross-section, used in connection with a head memberhaving a engaging blade.

FIG. 8 is a cross-sectional end view of that shown in FIG. 7.

FIG. 9 is a side view of a fastening system applied to a skin, meniscallayer, or other tissue break, according to the present invention.

FIG. 10 is a side view of a fastening system for use in attaching atendon to a bone according to the present invention.

FIG. 11 is a side view of a fastening system such as that shown in FIG.10 used to attach a tendon to a bone according to the present invention.

FIG. 12 is a detailed view of an anchoring member used to anchor afilament member to a bone according to the present invention.

FIG. 13 is a side plan view of a fastening system used to link two bonemembers together according to the present invention.

FIG. 14 is a lower plan view of a spiked head according to the presentinvention used to accept a plurality of filament members.

FIG. 15 is a side cross-sectional view of the head of FIG. 14,illustrating only two spikes.

FIG. 16 is a side view of an installation tool according to the presentinvention used to install fastening systems.

FIG. 17 is a side, partially cut away view of an installation needleaccording to the present invention used to install fastening systems.

FIG. 18 is an end cross-sectional view of the needle shown in FIG. 17.

FIG. 19 is a partial top planned view of a second installation needleaccording the present invention used to install fastening systems.

FIG. 20 is a cross-sectional view along line 20--20 of FIG. 19.

FIG. 21 is an in plan view of the needle illustrated in FIG. 19.

FIG. 22 is a partial cross-sectional view of a portion of the needleillustrated in FIG. 19, illustrating the use of the needle andinstalling a T-shaped member into a bone.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring now in more detail to the drawings, in which like numeralsindicate like parts throughout the several views, FIG. 1 illustrates afastening system 10, including an elongate flexible filament member 12,and a head member 14 slidably mounted thereupon. The filament member 12includes a plurality of uniformly spaced-apart protruding sectionsincluding protrusions 16. The filament member 12 also includes aplurality of uniformly spaced-apart reduced sections 17 intermediate theprotrusions 16. The engagement member 18 interferes with the protrusions16 of the filament of a greater degree than with the reduced sections 17of the filament.

Referring also to FIG. 2, the head member 14 defines an inner bore 15,which includes two bore portions "A" and "C" having substantiallyuniform and similar transverse cross sections, and an intermediate boreportion "B" having a transverse cross-section less in area than that ofbore portions "A" and "C", due to the existence of engagement member 18,which is intended to contact the protrusions 16. The protrusions 16 passwith relative ease through portions "A" and "C" of the bore 15, but theengagement member 18 contacts the protrusions within bore portion "B". Aprotrusion 16 will not pass by the engagement member until after a forcehas been applied by the protrusion against the engagement membersufficient to deflect or deform either the engagement member or theprotrusion, or a combination thereof, such that the protrusion can passby the engagement member.

As may be understood, as the filament member 12 is moved left to rightas shown in the drawings relative to head 14, protrusion 16a will be thefirst to contact and then pass by engagement member 18. This may also bereferred to as passing the engagement member across the protrusion.Subsequently, another protrusion 16b will encounter the engagementmember 18. During such a process, it may be understood that intermittentlevels of force will be required to draw the filament member 12 past theengagement member 18; just as the protrusions 16 are provided in agenerally uniformly spaced-apart relationship along the filament member12, so will various intermittent force "peaks" be required in order topass the filament member 12 through the head member 14.

Therefore it may be understood that filament members such as 12 may passthrough head members such as 14, with the above-described interferencetending to cause the engagement member 18 of the head to tend to remainbetween the protrusions and atop the reduced portions 17 such as shownin FIG. 2, unless a force is provided to overcome the above describedinterference. A head-sleeve relationship as shown in FIG. 2 is such thatit would be seen if a leftward force was applied to the head 14 and arightward force was applied to the filament 12, but said forces wereinsufficient to overcome the engagement between the engagement member 18and the protrusion 16b.

Referring now to FIG. 3, a fastening system 20 is shown, including ahead member 24 interacting with a filament member 22 having spaced-apartprotrusions 26, and spaced apart reduced portions 27.

The filament has a substantially circular cross-section, although theareas of such cross-section may vary depending on whether thecross-section is taken through the protrusions or reduced portions. Thehead member includes a main body defining a substantially circular hole(not shown) through which the filament passes, and also includes a pairof flange members 35, although three or more flange members may be used.The flange members 35 extend from the main body of the head member(extending left to right as shown in the drawings) and terminate todefine a shoulder 37 intended to contact the protrusions 36. The freeends of the flange members-may be seen to provide "engagement means" forengaging the protrusions 36 of the filament.

It may be understood that the free ends of flange members 35 aredeflected radially outwardly relative to the longitudinal axis of thefilament member 32 as the filament member is drawn left to rightrelative to the head 34 and the flange members pass across theprotrusions. It may also be understood that intermittent force "peaks"as discussed above are encountered, as the flange members 35 interferewith the protrusions 36 to a greater extent than with the reducedportions 32 of the filament member. It finally may be understood that ifthe filament member 32 is caused to move right to left relative to thehead 34, the shoulders 37 of the protrusions 36 will tend to preventsuch movement, and preferably much higher force "peaks" would beencountered in moving the filament right to left relative to the headcompared to the force peaks encountered in moving the filament left toright. In fact, it may not be possible to create such movement withoutdamaging either the filament or the head.

FIGS. 4-6 illustrate further filament-head configurations in whichprotrusions and reduced portions exist on the filaments.

FIGS. 7 and 8 illustrate a filament-head configuration in which afilament member 62 has a relatively smooth surface 63 which is engagedby an engagement member or blade 68 mounted within an internal holedefined by a head member 64. As the filament member 62 is moved left toright relative to the head member 64, the edge of the blade 68 whichcontacts the surface 63 of the filament member 62 slides across thesurface 63 of the filament member 62. However, should the filamentmember 62 be urged right to left relative to the head member 64, therelatively sharp nature of the blade 68 restricts such movement as theedge tends to engage or "bite into" the filament member. Therefore, itmay be seen that the configuration illustrated in FIG. 7 is such thatthe filament member-may move left to right relatively easily, but isdiscouraged from moving right to left relative to the head member 64.

It may be noted that the surface 63 of the filament member 62 may besmooth, or also may have a serrated surface to encourage engagement ofthe blade 68 into the filament member. Such a serrated configuration issimilar.

Other fastening systems including filament members used in non-medicalapplications, are disclosed in U.S. Pat. Nos. 3,290,080, Re. 27,357,3,973,299, and 4,245,374, all of which are incorporated by reference.

In the configurations shown in FIGS. 1-6, the transverse cross-sectionof the filaments at any position along their lengths is substantiallycircular. Therefore, a collar member may rotate about its associatedfilament member, but such rotation alone will not cause it to travellongitudinally along the filament member such as by a screw action. Inthe configuration shown in FIGS. 7 and 8, the rectangular transversecross-section of the filament 62 and the similarly-shaped inner slotdefined by the collar member 64 does not allow the collar to twistrelative to the filament. This non-twist feature may be advantageous inthe collar (or a washer affixed thereto) may be positioned against atendon or ligament as discussed below, and rotation of the collar may bereduced or prevented.

The above-discussed filaments and heads may be made of inert materialssuch as polyethylene, nylon, or other suitable polymeric materials, ifthe connection is desired to be permanent. If the connection is desiredto be temporary, degradable materials such as polyglactin (providedunder the trade name VICRYL, or polydioxanone (PDS) may be used.

As shown above, many different fastening systems including filaments andheads are disclosed in reference to FIGS. 1-8. These fastening systemsmay be used interchangeably in many of the following applications to thesurgical field.

Referring now to FIG. 9, a filament member 72 is used in combinationwith a pair of head members 74, in order to provide a suture to mend abreak in human or animal tissue 75 such as that at 76. The tissue membermay, for example, be a meniscal layer or a skin layer.

The filament member 72 is threaded through two adjoining tissue portionson opposing sides of the tissue break 76, much as a typical thread wouldbe attached to a needle and passed through such tissue members in orderto mend them by a typical stitch.

After the filament member 72 has been passed through the tissue and eachof its ends extend above one side of the tissue (preferably the outersurface of skin tissue), the head members may then be placed on each endof the filament members and then urged toward the center of thefilament, until the head members are adjusted to contact the tissuesurface layer at 77, and until a desired tautness of the filament member72 between the head members is obtained. At this time, any excessfilament length extending above the heads may be trimmed as desired.Other similar sutures could be provided depending on the size and lengthof the tissue break.

It should be understood that the two portions of the filament whichactually lie within the tissue layer may be understood to be "inside"the tissue. If the tissue is skin, the head members would preferably beon the "outside" of the skin (the side exposed to the elements), biasingon the "outside" surface of the skin.

It should also be understood that another installation method may beused to arrive at the configuration shown in FIG. 9. One head member 74may be placed on one end of the filament member 72 prior to insertion ofthe filament into the tissue, with the opposing end of the filament thenbeing passed through both of the tissue portions. At that time, only onehead member would be required to be placed on the other end of thefilament member.

Furthermore, also contemplated is the use of a fixed "head" (not shown),attached to one end of the filament to replace one of theabove-described heads illustrated in FIG. 9. Such a configuration wouldrequire only one adjustable head to be placed on one end of thefilament, after the filament has been passed through the tissue. Such afixed head could be as that known as a ZIMMER STATAK device availablefrom Zimmer, Inc., P.O. Box 708, Warsaw, Ind., 46590-0708, illustratedin catalog no. 2344-10, disclosed in U.S. Pat. No. 4,632,100 andincorporated herein by reference.

Note that alternate configurations could be used to attached the tissueat its break described above. For example meniscal or skin layers couldbe overlapped, with a fixed T-shaped head (discussed in further detailbelow) attached to one end of the filament and forced through theoverlapped tissue, with a head member subsequently placed on thefilament end opposite the T-shaped head and pushed toward the T-shapedhead to squeeze the overlapped skin therebetween. In such aconfiguration, the filament portion intermediate the two heads wouldpreferably be in tension and substantially straight. Such aconfiguration would be especially qualified for use with arthroscopictechniques.

Referring now to FIGS. 10 and 11, a filament member 82 is used incombination with an anchor member 83 and a head member 84 in order tomaintain a tissue member 86 such as a tendon or ligament in surfacecontact with a bone 88. The anchor member 83 is attached to one end ofthe filament member. Installation of the anchor member into the boneallows the filament member 82 to be attached to the bone 88 approximatethe area at which the tissue is desired to be attached to the bone 83.

After installation of the anchor member, the filament member 82 isthreaded through tissue member 86 (piercing it if necessary) issubsequently threaded through a washer 89, and finally is threadedthrough a head member 84 such as that described as 24 in the fasteningsystem shown in FIG. 3. At that point, the filament 82 is preferablymaintained in a tensile state by pulling on it while the head 84 ispushed along the filament 82 (such that the engagement member or membersof the head 84 pass by the protrusions on the filament 82) until thetissue is snug against the surface 90 of the bone 88, the washer 89 issnug against the tendon 86, and the head 84 is snug against the washer89. Such snugness is provided by the virtue of engagement of theengagement member of the head with one of the protrusions. Excessfilament may then be trimmed.

It may be understood that a separate washer 89 may be used as describedabove, or another type of head may be used which incorporates anintegral flange which serves the same purpose of the above-describedwasher.

As shown in FIG. 10, the washer may include a plurality of spikes 87,which may be used to engage the tissue to prevent slippage. The size andconfiguration of the spikes may vary depending on the nature of theparticular application.

As shown in FIGS. 14 and 15, a multi-filament head 101 may be used whichincludes a plurality of one-way holes 103 for accepting a plurality offilaments such as 104 which have been affixed in a localized boneregion. Such an application may be advantageous in situations where alarge or broad tissue member is to be affixed to a bone. Suchmulti-filament configurations may also be used if it is not desired topierce the tissue member; two filament members could be used to attach ahead atop a tissue member, with the filament members being positioned oneither side of the; tissue without piercing it.

Referring now to FIG. 12, a filament 92 is used in combination with apair of externally-threaded anchor members 94. Referring also to FIG.13, the anchor members 94 are screwed into respective cavities 95drilled into bone members 97. The anchor members 94 each have a centrallongitudinal bore 93 which passes entirely through each anchor member94. Within the bore 93 extends at least one engagement member 99 whichinteracts with protrusions 96 defined by filament 92 as discussed above.Note that instead of the engagement member 99 being positioned within ahead such as that described above, the engagement member is positionedwithin the internal bore of 93 the anchor member, which accepts thefilament 92.

When both of the anchor members 94 are positioned within holes 95 in therespective bone members 97, each end of the filament member 92 is placedwithin a respective anchor member 94. At that time, the filament member92 is pushed into the anchor members 94 until a desired length of thefilament extending between the bones is obtained. As the bores 93 extendcompletely through the anchor members 94, there is some space for theends of the filament 92 to pass through the anchor member and into theend of the cavity 97 drilled into the bone. As the filament member ispreferably somewhat flexible, it may even be possible that although oneend of the filament member may "bottom out" in the cavity, it couldstill be able to be pushed further into the cavity, as it may fold overitself or bend.

An alternative configuration to that shown in FIG. 13 includes a pair ofanchor members, but with only a first anchor member including aninternal engagement means as described above. The second anchor memberis affixed to one end of the filament, with no adjusting capability. Insuch a configuration, the filament will only be adjusted within theanchor member including the engagement means.

Referring now again to FIGS. 1-6, various filaments and heads are shown.It may understood that these heads are what may be termed as "one-way"or "two-way" heads, and some of the filaments may be understood as"one-way" or "two-way" filaments.

Referring to FIGS. 1 and 2, filament 12 may be referred to a "two-way"filament, as its protrusions 16 are configured such that a head passingin one direction along the filament will encounter substantially thesame resistance than the head passing in a second, opposite direction.This is of course assuming that the restricted portion of the head boreencountering the protrusions is the same, such as the case with head 14,which may be referred to as a "two-way" head. It may be understood thatsuch a configuration is such that the engagement member and theprotrusion member interact such that the maximum force required to urgethe engagement member by a protrusion in one direction is approximatelythe same as the maximum force required to urge the engagement member bythe protrusion in a second, opposing, direction.

Referring now to FIGS. 3 and 4, filament 32 may be considered a"two-way" filament. However, the head 34 positioned thereon may beconsidered a "one-way" filament, as such a head moving left to rightrelative to the filament will encounter more resistance than the samehead moving right to left. Such a configuration is at times preferablewhen one wishes to move such a head in one direction, but does not wishthe head to move in the opposite direction. It may be understood thatsuch a configuration is such that the engagement member and theprotrusion member interact such that the maximum force required to urgethe engagement member by a protrusion in one direction is less than themaximum force required to urge the engagement member by the protrusionin a second, opposing, direction.

Using the above criteria, FIG. 5 illustrates a "one-way" head is shownpositioned on a "one-way" filament 42.

In reference to FIG. 6, a "one-way" head is shown positioned on a"two-way" filament.

In reference to FIGS. 7 and 8, the filament 62 may be considered a"two-way" filament, while the head positioned thereon may be considereda "one-way" head.

Referring now to FIG. 16, an installation tool 110 is illustrated foruse is urging a typical head 114 along a typical filament 112, such thatthe head moves in a right to left direction relative to the filament112. The installation tool 110 includes a trigger 111, and a force gauge120, which is read to determine the mount of force used to draw thefilament 112 through the collar 114.

It should be understood that such force is needed to overcome theabove-discussed requirements of deflecting any engagement members withinthe collar 114, but an opposing tensile force on the filament 112 mayalso be present if the filament has been attached to a bone or has been.threaded through tissue as described above.

An illustration of the use of the installation tool 110 is now describedas such a tool might be used in order to affix the tendon 86 to the bone88 as shown in FIG. 11. The filament 82 would be inserted into a hole(not shown) in the "nose" of the installation tool 110, and an internalmechanism including a pair of grasping sprockets 115 would cooperate tograsp that end of the filament.

The grasping sprockets are mounted for driven rotation aboutsubstantially parallel spaced-apart axes, such that radially extendedteeth of each sprocket cooperate to bias against protrusions of afilament in order to draw the ligament into the tool. The tool may beconfigured to work with any of the filaments and heads shown in FIGS.1-6. For use in connection with the filament and head shown in FIGS. 7and 8, the means for grasping the filament would need to be modified.

When the filament 82 is in proper position within the tool, the trigger111 of the tool 110 is pulled, causing the internal mechanism to pull onthe filament, such that it is caused to drown into the tool. When thecollar finally contacts the nose of the tool 110 (such as the collar 114is contacting the tool in FIG. 16), the movement of the collar relativeto the tool 110 will be prevented, thus causing the filament to be dramthrough the collar 114.

At this time, the operator will monitor the force gauge 120. Asdiscussed above, eventually the nut 84 is pushed into contact with thewasher 89, and the washer 89 is pushed into contact with the tendon 86,which is likewise urged against the surface 90 of the bone 88. As suchelements are drawn close together such as shown in FIG. 11, the operatorwill monitor the force dial 120 with care. Depending on his or herexperience with the particular ligament or tendon being attached to thebone, the operator will recognize when a desired force is read on thedial, and will then terminate operation of the tool. The tool will thebe withdrawn, and the filament may be trimmed as discussed above. Thegun may optionally have an internal mechanism which recognizes a pre-setforce exerted on the filament, and will automatically disengage at thatpoint. The gun may also optionally have a filament cutting mechanism.

Another contemplated use of filaments in the surgical field is shown inFIGS. 17 and 18. A slotted needle 130 includes an elongate slot 131running along its length. A filament 132 includes a T-shaped head 133attached to one of its ends. This head may loaded into the slot of theneedle 130 and placed in end-to-end contact with a urging pin 134 whichis configured to slide within the slot 131 of the needle. After the tip135 of the needle 130 has been passed through one or more layers oftissue (not shown), an urging mechanism (not shown) is activated suchthat the urging pin 134 pushes the head 133 of the filament (leftto-fight in reference to FIG. 17) such that the head exits the needle,straightens out, and is positioned on one side of the tissue resistingretraction therethrough, while the opposing end of the filament is onthe opposite side of the tissue. If the filament has been passed throughtwo layers of tissue (such as shown in FIG. 9), a cooperating head suchas 24 shown in FIG. 3 may be placed on the filament and pushed along thefilament as discussed above such that the two tissue members may beattached via the filament-heads combination.

Such a configuration as shown in FIGS. 17 and 18 is especially suitablefor use during arthroscopic procedures, by the use of specially designedinsertion tools (not shown). It may be understood that the relativelysimple fastening configuration provided by the invention would notrequire unduly complex arthroscopic tools.

Referring now generally to FIGS. 19-22, a second installation needlesystem 150 is disclosed, which includes a sleeve 151, and an internalstyler 152, which slidably fits within a slot defined by the sleeve 151.The sleeve and the stylet combine as shown in FIG. 19 to form agenerally cylindrical, pointed member, in which the point is generallydefined by three faces meeting at edges 155 (see also FIG. 21). Thesystem 150 may used to attach a tendon 160 to a bone including acortical bone wall 162, and internal cancellous bone 163. The cancellousbone is softer than the conical bone.

Referring now to FIG. 22, in order to fasten the tendon or other tissue160 to the bone, the point of the needle system 150 is passed throughthe tendon 160, and thereafter driven or rotated into the bone, suchthat the tip of the needle system 150 passes through the cortical wall162. At that point, the styler is withdrawn from the sleeve, and thehead 164 of a T-shaped member 165 is placed within the slot. Thereafter,a driving member 167 is activated in order that the head is driventhrough the sleeve, past the cortical bone, and into the cancellous boneregion. It may be seen that the curved portion 170 defined by the sleeveurges the leading tip 171 of the head of the T-shaped member in anupward direction away from the installation axis of the head.

After the head 164 is installed within the cancellous bone region, thesleeve 151 is withdrawn. It may be understood that as the T-shapedmember has been urged in the above-referenced upward direction, asubsequent pull on the filament 172 will cause the "T" to lie snug andflat against the inside surface of the cancellous bone 162, and it willbe discouraged from being subsequently withdrawn through the hole leftby the needle system 150. Alternatively, the cancellous bone could be ofsufficient stiffness to capture the "T" on its own, such that the "T"may not be positioned against the inside surface of the cortical bone.After the "T" is in place, a head member (not shown) may be placed uponthe filament portion 172 of the T-shaped member 165, as described above.Note that the close proximity of the projections on the filament member172 still provide for intermediate reduced portions, and such aconfiguration is contemplated under the present invention.

Therefore, it may be seen that methods and apparatuses for attachingtendons, ligaments, or other tissue to bones is provided which do notrequire drastic drilling or other bone access preparations, and may besuitable for arthroscopic applications. Unlike some prior art methods,there is no need to drill completely through the bone. Unlike otherprior methods, simple devices and methods are provided which includeminimal parts and complexity.

Therefore, it may be seen that the present invention provides methodsand apparatuses for providing reliable, simple, and effective means forreattaching tendons, ligaments, or other tissue which have becomeseparated from the bone of a human or animal. The invention alsoprovides a means for providing a suture in order to mend a break in askin layer, a meniscal layer, or other tissue. The methods andapparatuses allow a surgeon or other qualified personnel to expedientlyperform repair procedures, using arthroscopic procedures if possible, inorder that the patient undergoes minimal trauma as well as experiencesminimal infection or scarring due to a reduced need for incision.

It should be understood that the foregoing relates only to preferredembodiments of the present invention, and that numerous modifications oralterations may be made therein without departing the spirit and scopeof the invention as set forth in the appended claims.

What is claimed is:
 1. A device for attaching an elongate, flexiblefilament member to a bone, said bone defining a pre-drilled bone holetherein, comprising:an elongate flexible filament and an anchor memberdefining an external surface configured to engage said pre-drilled bonehole and secure said anchor member relative to said hole, said anchormember also defining an internal bore to be substantially aligned withsaid hole and configured to accept a length of said filament member,said anchor member also defining an internal engagement means configuredto engage said length of said flexible filament member within saidanchor to discourage removal of said filament from said anchor when itis in place in said bone.
 2. The device as claimed in claim 1, whereinsaid filament member includes a plurality of protruding portionsseparated by reduced portions, and wherein said anchor member bore is acentral longitudinal bore, and said engagement means is configured toengage said protruding portions to a greater extent than said reducedportions, to allow said filament to be secured at a variety of positionsrelative to said anchor member.
 3. The device as claimed in claim 2,further comprising a head member configured for attachment to saidfilament member to facilitate securement of tissue relative thereto. 4.The device as claimed in claim 2, further comprising a second anchormember configured for attachment relative to said filament member tofacilitate securement of tissue relative thereto.
 5. The device asclaimed in claim 1, further comprising a head member configured forattachment to said filament member to facilitate securement of tissuerelative thereto.
 6. The device as claimed in claim 1, furthercomprising a second anchor member configured for attachment relative tosaid filament member to facilitate securement of a second bone memberrelative thereto.
 7. A device for attaching a first bone to a secondbone, said first bone defining a pre-drilled bone hole therein, saiddevice comprising:an elongate, flexible filament member, a first anchormember defining an external surface configured to engage saidpre-drilled hole and secure said anchor member relative to said firstbone, said anchor member also defining an internal bore to besubstantially aligned with said pre-drilled hole and configured toaccept a first end of said filament member, said anchor member alsodefining an engagement means configured to engage said flexible filamentmember within said first anchor have to discourage removal of saidfilament from said first anchor member when in place in said bone; and asecond anchor member for attaching said second end of said filamentmember to said second bone.
 8. The device as claimed in claim 7, whereinsaid second bone also defines a pre-drilled second hole therein, andwherein said second anchor member defines an external surface configuredto engage said pre-drilled second hole and secure said anchor memberrelative to said second bone, said second anchor member also defining aninternal second bore substantially aligned with said pre-drilled holeand configured to accept a second length of said filament member, saidsecond anchor member also defining an engagement means configured toengage said second length of said flexible filament member within saidsecond anchor have to discourage removal of said filament from saidsecond anchor member when in place in said bone.
 9. The device asclaimed in claim 8, wherein said filament member includes a plurality ofprotruding portions separated by reduced portions, and wherein saidfirst anchor member bore is a central longitudinal bore, and saidengagement means of said first anchor member is configured to engagesaid protruding portions to a greater extent than said reduced portions,to allow said filament to be secured at a variety of positions relativeto said first anchor member.
 10. The device as claimed in claim 7,wherein said filament member includes a plurality of protruding portionsseparated by reduced portions, and wherein said first anchor member boreis a central longitudinal bore, and said engagement means of said firstanchor member is configured to engage said protruding portions to agreater extent than said reduced portions, to allow said filament to besecured at a variety of positions relative to said first anchor member.11. The anchor member as claimed in claim 10, wherein said externalsurface of said first anchor member is threaded to facilitate threadedengagement with said pre-drilled hole in said bone.
 12. The anchormember as claimed in claim 7, wherein said external surface of saidfirst anchor member is threaded to facilitate threaded engagement withsaid pre-drilled hole in said bone.
 13. A device for attaching tissue tobone, comprising:a filament member defining opposing first and secondends and including a first protruding portion, a first reduced portionhaving a cross-sectional area less than that of said protruding portion,said reduced portion located intermediate said first end and said firstprotruding portion, said filament also including a threadable portioncapable of being threaded through said tissue, said threadable portionbeing intermediate said first end and said reduced portion; an anchormember located at said first end for attaching said first end of saidfilament member to said bone; and a head member movable relative to saidfilament and defining an internal hole extending therethrough foraccepting said filament and also defining engagement means extendinginto said hole, said engagement means configured to engage said firstportion to a greater extent than said first reduced portion, saidengagement member engaging said protrusion and restricting movement ofsaid head member toward said second end of said filament member and saidhead member likewise restricting movement of said tissue away from saidbone.
 14. The device as claimed in claim 13, wherein said anchor memberdefines a central longitudinal bore to allow said filament to be securedtherein at a variety of positions relative to said anchor member. 15.The device as claimed in claim 13, wherein said filament member includesa plurality of protruding portions separated by reduced portions, andwherein said anchor member defines a central longitudinal bore includingengagement means therein configured to engage said protruding portionsto a greater extent than said reduced portions, to allow said filamentto be secured at a variety of positions relative to said anchor member.